I'm thinking about finding expired tumblr blogs, signing up and automating reblog/upload to build backlinks to the Tumblr blog. As long as I continue to post, I reckon the Tumblr blog will get internal links from other blogs. I already own one with PA43 so it seems to be working. Once they get value, my plan was to link to my PBN. Is this possible though without leaving a huge footprint and risk hurting my PBN? Since I continue to post on the Tumblr blogs, I can't leave a single blog post with a link so I would probably have to add the link in the theme sidebar and get a link from every page on the blog, something I really don't want to do. Any ideas or should I just give up Tumblr?